Add code coverage to build

Author: gcurtis

build.gradle

@@ -1,5 +1,6 @@
 apply plugin: 'checkstyle'
 apply plugin: 'java'
+apply plugin: 'jacoco'
 
 sourceCompatibility = 1.7
 
@@ -38,6 +39,11 @@ tasks.withType(Test) {
         exceptionFormat = 'full'
         testLogging.showStandardStreams = true
     }
+
+    jacoco {
+        append = true
+        destinationFile = file("$buildDir/jacoco/test.exec")
+    }
 }
 
 test {